Our childhood shapes the way we see the world, and people often grow up thinking that rare medical conditions, weird family traits, and peculiar misconceptions are shared by their peers. It isn't until they get older that they realize some beliefs and absurdities are unique only to them.
Here are things that various Reddit users grew up accepting as common sense until they had a major realization.
Saying "open" and "close" the lights.

"I say 'close' or 'open' lights instead of turn 'on' or 'off.' I never noticed it was wrong until someone pointed it out in high school."— Reddit user MCML
Wrapping a towel around your body.

"I was raised by my mom and two older sisters. Whenever they showered, they put the towel around their whole body, so naturally, I did, too. It never occurred to me to just put the towel around my waist … "— Reddit user darthaugustus
Seeing all things as blurry.

"[I thought it was normal for] stuff to get blurrier the further away it is. It seemed to make sense — it's further away, so I can't see it as well. It wasn't until I was 18 and sitting in the back of massive lecture halls when I noticed that the people sitting next to me could read the board just fine. Then, I realized I needed glasses."— Reddit user eketros
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